210221020 has 48 divisors (see below), whose sum is σ = 451207008. Its totient is φ = 82252800.

The previous prime is 210221003. The next prime is 210221027. The reversal of 210221020 is 20122012.

It is a Harshad number since it is a multiple of its sum of digits (10).

It is a junction number, because it is equal to n+sod(n) for n = 210220988 and 210221006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (210221027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 199495 + ... + 200545.

It is an arithmetic number, because the mean of its divisors is an integer number (9400146).

Almost surely, 2^210221020 is an apocalyptic number.

210221020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

210221020 is an abundant number, since it is smaller than the sum of its proper divisors (240985988).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

210221020 is a wasteful number, since it uses less digits than its factorization.

210221020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1270 (or 1268 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 10.

The square root of 210221020 is about 14499.0006552176. Note that the first 3 decimals coincide. The cubic root of 210221020 is about 594.6006500400.

Adding to 210221020 its reverse (20122012), we get a palindrome (230343032).

The spelling of 210221020 in words is "two hundred ten million, two hundred twenty-one thousand, twenty".